Date of introduction: 1972.
Date of withdrawal: 1978.
Technology: an OMNIBUS machine, as with the PDP-8/E. First use
of a switching power supply in the PDP-8 family.
Reason for introduction: The PDP-8/E had a large enough box and a large
enough power supply to accomodate a large configuration. By
shortening the box and putting in a small switching power supply,
a lower cost OMNIBUS machine was possible.
Reason for withdrawal: The PDP-8/A 800 displaced this machine, providing
similar expansion capability at a lower cost.
Compatability: The PDP-8/F used the PDP-8/E CPU and peripherals.
Standard configuration: Identical to the PDP-8/E, except that the KC8E
front panel was replaced with a KC8M front panel that had LEDs
instead of incandescent lights; this front panel could also be
installed on PDP-8/E systems, but the PDP-8/E front panel could
not be used on a PDP-8/F because of the lack of a +8 supply for
the lights. The original PDP-8/F box had a defective power
supply, but a revised (slightly larger) box corrected this
problem.
With the dintroduction of the M8330, DEC began to require that
this board be placed adjacent to the KC8x front panel, although
many OMNIBUS PDP-8 systems continued to be configured (by users)
with the M8330 elsewhere on the bus. As a result, the suggested
order of boards on the omnibus began with:
-- KC8E programmer's console (lights and switches)
-- M8330 - Timing board (system clock)
-- M8340 \_ optional EAE board 1
-- M8341 / optional EAE board 2
-- M8310 \_ KK8E CPU control
-- M8300 / KK8E CPU registers
-- M837 - Extended Memory & Time Share control
Expandability: This machine could be expanded using all PDP-8/E OMNIBUS
peripherals, including the external expansion chassis. The
relatively small internal power supply and the lack of room for
a 20 slot bus expander inside the first box were the only
limitations. There were minor compatability problems with some
options, for example, the power-fail auto-restart card, as
originally sold, was incompatable with the PDP-8/F power supply.
Survival: As with the PDP-8/E, these machines are moderately common on
the surplus market, and frequently in working condition.

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